Fluorination of acetals, ketals and orthoesters

ABSTRACT

This invention pertains to perfluoropolyethers and perhalogenated chlorofluoroether polymers that can be prepared by fluorinating polymers made by the polymerization of acetals, ketals, polyacetals, polyketals and orthoesters with elemental fluorine.

RELATED PATENT APPLICATIONS

This application is a division of application Ser. No. 08/222,797 filedApr. 5, 1994, now allowed, which is a continuation of U.S. patentapplication Ser. No. 07/966,681, filed Oct. 26, 1992, which issued asU.S. Pat. No. 5,300,683 on Apr. 5, 1994, which is a continuation of U.S.patent application Ser. No. 07/752,703, filed Aug. 30, 1991, whichissued as U.S. Pat. No. 5,202,480 on Apr. 13, 1993, which is acontinuation of U.S. patent application Ser. No. 07/413,785, filed onSep. 28, 1989, which issued as U.S. Pat. No. 5,053,536 on Oct. 1, 1991,which is a continuation-in-part of U.S. patent application Ser. No.07/250,384, filed on Sep. 28, 1988, now abandoned, all of which areincorporated herein by their entirety.

BACKGROUND OF THE INVENTION

Perfluoropolyethers are highly regarded in the specialty lubricant fieldbecause of their wide liquid ranges, low vapor pressures and highthermal and oxidative stabilities. Because of these properties, (many ofwhich are unique to fluorocarbons) they are excellent high performancelubricants, superior base stocks for greases, excellent lubricatingoils, and heat transfer fluids. In addition, because of these uniquelyoutstanding properties, saturated perfluoropolyethers are of currentinterest as specialty sealants, elastomers and plastics.

In spite of their unlimited potential, only three perfluoropolyethersare commercially available to date because of the lack of fluorocarbonintermediates which are suitable for preparing the polymers. They are

1. DuPont's Krytox™ fluid which is made by polymerizinghexafluoropropylene oxide;

2. Demnum™ fluid, a product of Daikin, is obtained by ring openingpolymerization of 2,2,3,3-tetrafluorooxetane using a catalyst withsubsequent treatment of the highly fluorinated polyether with fluorinegas to give a perfluorinated product; and

3. Monticatini Edison's Fomblin Z™ and Fomblin Y™ fluids which areprepared by photooxidizing tetrafluoroethylene and hexafluoropropyleneoxide, respectively, in the presence of oxygen.

A process has been described for preparing perfluoropolyethers byreaction of a hydrocarbon polyether with elemental fluorine in thepresence of a hydrogen fluoride scavenger. See U.S. Pat. No. 4,755,567.

SUMMARY OF THE INVENTION

This invention relates to perfluorinated polyethers of the formula:##STR1## wherein Y and Y' are the same or different and are selectedfrom the group consisting of perfluoroalkyl, perfluoroalkylether andperfluoroalkylpolyether wherein fluorine may be substituted with one ormore halogen groups other than fluorine; wherein R₁ and R₂ are the sameor different and are selected from the group consisting of --F, --Cl,--CF₂ Cl, --CFCl₂, --CCl₃, perfluoroalkyl of one to ten carbons; whereinfluorine may be substituted with one or more halogen groups other thanfluorine and wherein the perfluoroalkyl group may contain one or moreether oxygens. The perfluoroalkyl polyether which is Y and Y' may beatactic, isotactic or a block copolymer having 1 to 50 carbon atoms.

In another embodiment of the previous formula, when Y or Y' have 20 orfewer carbon atoms and R₁ is fluorine then R₂ is a group other than--CF₃ or --CF₂ Cl.

This invention pertains to perfluorinated polyethers having the formula:##STR2## wherein R₁, R₂ and R₃ are the same or different and areselected from the group consisting of --F, --Cl, --CF₂ Cl, --CFCl₂,--CCl₃, perfluoroalkyl of one to ten carbon atoms andperfluoroalkoxyalkyl of one to ten carbon atoms wherein one or more ofthe fluorine atoms may be substituted by a halogen atom other thanfluorine; wherein X and Z are the same or different and are selectedfrom the group consisting of --(CF₂)_(r) COF, --(CF₂)_(r) OCF₃,--(CF₂)_(r) COOH and --C_(r) F_(2r+1-q) Cl_(q) wherein r is an integerfrom 1 to 12 and q is an integer from 0 to 25; p is an integer from 1 to50. In a preferred embodiment, R₁, R₂ and R₃ are F, and p is an integerbetween 2 and 50.

This invention further relates to perfluorinated polyethers of theformula: ##STR3## wherein X and Z are the same or different and areselected from the group consisting of --(CF₂)_(r) COF, --(CF₂)_(r) OCF₃,--(CF₂)_(r) COOH and --C_(r) F_(2r+1-q) Cl₁, wherein r is an integerfrom 1 to 12 and q is an integer from 0 to 25; wherein R₁ and R₂ are thesame or different and are selected from the group consisting of --F,--Cl, --CF₂ Cl, --CFCl₂, --CCl₃, perfluoroalkyl of one to ten carbonatoms and perfluoroalkoxyalkyl of one to ten carbon atoms wherein one ormore of the fluorine atoms may be substituted by a halogen atom otherthan fluorine; and provided that R₁ and R₂ together are not F.

The perfluoropolyethers and the perhalogenated chlorofluoropolyethers ofthis invention can be used as lubricants, hydraulic fluids, thermalshock fluids, vapor phase soldering fluids and in numerous otherapplications in which an inert, nonflammable, oxidatively stable fluidis required. The low molecular weight perfluoropolyethers of the presentinvention have many useful applications in the electronics industry.

DETAILED DESCRIPTION OF THE INVENTION

This invention pertains to perfluorinated polyethers having the formula:##STR4## wherein Y and Y' are the same or different and are selectedfrom the group consisting of perfluoroalkyl, perfluoroalkylether andperfluoropoxy(alkyleneoxy)alky; wherein fluorine may be substituted withone or more halogen groups other than fluorine; wherein R₁ and R₂ arethe same or different and are selected from the group consisting of --F,--Cl, --CF₂ Cl, --CFCl₂, --CCl₃ and perfluoroalkyl having 1 to 20 carbonatoms; and wherein the perfluoroalkyl group may contain one or moreether oxygens. The perfluoroalkylpolyether may be atactic, isotactic ora block copolymer having 1 to 50 carbon atoms. Examples of two polymersof this formula are Y--O--CF₂ --OY and Y--O--CF--(CF₃)--OY wherein Y isthe same.

In another embodiment, this invention pertains to perfluorinatedpolyethers having the formula: ##STR5## wherein X and Z are the same ordifferent and are selected from the group consisting of --(CF₂)_(r) COF,--(CF₂)_(r) OCF₃, --(CF₂)_(r) COOH and --C_(r) F_(2r+1-q) Cl_(q),wherein r is an integer from 1 to 12 and q is an integer from 0 to 25;wherein R₁ and R₂ are the same or different and are selected from thegroup consisting of --F, --Cl, --CF₂ Cl, --CFCl₂, --CCl₃, perfluoroalkylof one to ten carbon atoms and perfluoroalkoxyalkyl of one to ten carbonatoms wherein one or more of the fluorine atoms may be substituted by ahalogen atom other than fluorine; and provided that R₁ and R₂ togetherare not F.

This invention pertains to perfluorinated polyethers having the formula:##STR6## wherein R₁, R₂ and R₃ are the same or different and areselected from the group consisting of --F, --Cl, --CF₂ Cl, --CFCl₂,--CCl₃, perfluoroalkyl of one to ten carbon atoms andperfluoroalkoxyalkyl of one to ten carbon atoms wherein one or more ofthe fluorine atoms may be substituted by a halogen atom other thanfluorine; wherein X and Z are the same or different and are selectedfrom the group consisting of --(CF₂)_(r) COF, --(CF₂)_(r) OCF₃,--(CF₂)_(r) COOH and --C_(r) F_(2r+1-q) Cl_(q) wherein r is an integerfrom 1 to 12 and q is an integer from 0 to 25; p is an integer from 1 to50. In a preferred embodiment, R₁, R₂ and R₃ are F, and p is an integerbetween 2 and 50.

In another embodiment, this invention pertains to perfluorinatedpolyethers having the formula:

    Y--O--CF.sub.2 --O--Y'

wherein Y and Y' are the same or different and are selected from thegroup consisting of perfluoroalkyl, perfluoroalkoxyalkyl andperfluoroalkyleneoxyalkyl; and wherein the polyether comprises fewerthan 8 or greater than 12 or more carbon atoms provided that Y and Y'cannot both be --CF₃ or --C₂ F₅. In a preferred embodiment, thepolyether comprises from 12 to 20 carbon atoms.

In another embodiment, the invention includes perfluorinated polyethershaving the formula: ##STR7## wherein Y and Y' are the same or differentand are selected from the group consisting of perfluoroalkyl,perfluoroalkoxyalkyl and perfluoroalkyleneoxyalkyl; wherein R₁ and R₂are the same or different and are selected from the group consisting of--Cl, --CF₂ Cl, --CFCl₂, --CCl₃, perfluoroalkyl having 1 to 20 carbonatoms and perfluoroalkyleneoxyalkyl; and wherein the polyether comprises12 or more carbon atoms. In a preferred embodiment, the polyethercomprises 12 to 25 carbon atoms.

In another embodiment, the invention includes the perfluorinatedpolyethers having the formula: ##STR8## wherein Y and Y' are the same ordifferent and are selected from the group consisting of perfluoroalkyl,perfluoroalkoxyalkyl and perfluoroalkyleneoxyalkyl; wherein R isselected from the group consisting of --Cl, --CF₂ Cl, --CFCl₂, --CCl₃,perfluoroalkyl having 1 to 20 carbon atoms andperfluoroalkyleneoxyalkyl; and wherein the polyether comprises 12 ormore carbon atoms. In a preferred embodiment, the polyether comprises 12to 25 carbon atoms.

In another embodiment, the invention includes the perfluorinatedpolyethers having the formula: ##STR9## wherein Y and Y' are the same ordifferent and are selected from the group consisting of perfluoroalkyl,perfluoroalkyleneoxyalkyl and perfluoropoly(alkyleneoxy)alkyl, whereinone or more of the fluorine atoms may be halogen atoms other thanfluorine; wherein R₁ and R₂ are the same or different and are selectedfrom the group consisting of --F, --Cl, --CF₂ Cl, --CFCl₂, --CCl₃ andperfluoroalkyl having 1 to 20 carbon atoms wherein one or more of thefluorine atoms may be halogen atoms other than fluorine and wherein theperfluoroalkyl group may contain one or more ether oxygen atoms.

In another embodiment, the invention includes the perfluorinatedpolyethers having the formula: ##STR10## wherein Y and Y' are the sameor different and are selected from the group consisting ofperfluoroalkyl, perfluoroalkoxyalkyl and perfluoroalkyleneoxyalkyl,wherein R₁ and R₂ are the same or different and are selected from thegroup consisting of --F, --Cl, --CF₂ Cl, --CFCl₂, --CCl₃, perfluoroalkylhaving 1 to 20 carbon atoms and perfluoroalkyleneoxyalkyl; and whereinthe polyether contains at least one halogen atom other than fluorine.

This invention further pertains to a method of making perfluoropolyetherand perhalogenated chlorofluoropolyether polymers.

The reaction of a diol with either an aldehyde, acetal, ketal ortrialkyl orthoesters can be used to give a polyether if the startingmaterials and reaction conditions are carefully chosen. For example, ifan aldehyde such as formaldehyde, acetaldehyde or butyraldehyde isreacted with a diol, a linear polyether can be made. Such a reaction isshown in Formula 1 below: ##STR11## Suitable diols include ethyleneglycol, diethylene glycol, triethylene glycol, tetraethylene glycol,other higher polyethylene glycols, propylene glycol, dipropylene glycol,tripropylene glycol, 2,2-dimethyl 1,3-propanediol, 1,4-butanediol,1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol,1,9-nonanediol, and 1,10-decanediol. Suitable aldehydes includeformaldehyde, paraformaldehyde, 1,3,5-trioxane, acetaldehyde and itstrimer, butyraldehyde and its trimer, pentanal, hexanal, 2-ethylbutanal, chloroacetaldehyde, dichloroacetaldehyde andtrichloroacetaldehyde.

An alternative means of preparing the same polymer involves the reactionof an acetal with a diol. The synthesis involves the initial preparationof an acetal by reaction of an alcohol with the aldehyde as shown inFormula (2) below:

    RCHO+2R'OH→(R'O).sub.2 C(R)H+H.sub.2 O              (2)

The acetal interchange is followed by a smoothly reversible reaction inacid media giving rise to the polyacetal. This reaction is given inFormula (3) below:

    (R'O).sub.2 C(R)H+HO(CH.sub.2).sub.n OH→HO((CH.sub.2).sub.n OC(R)HO).sub.x H+2R'OH                                    (3)

Suitable acetals include the diethyl, dipropyl, dibutyl, dipentyl anddiphenyl acetals of all of the previously mentioned aldehydes.

A well known reaction which is particularly well suited for preparingcopolymers of acetaldehyde involves the reaction of divinyl ethers withdiols. For example, ethylene glycol divinyl ether will react withethylene glycol in the presence of H at -10° C. to give a 1:1 copolymerof ethylene glycol and acetaldehyde. Similarly, the divinyl ether of1,5-pentanediol will react with 1,5-pentanediol to give a copolymer ofpentanediol and acetaldehyde: ##STR12## Terpolymers can be prepared byreacting a divinyl ether of one diol with a diol of a differentstructure. For example, the divinyl ether of ethylene glycol will reactwith 1,3-propanediol to yield a polyether after fluorination having thefollowing structure: ##STR13## The divinyl ethers are convenientlyformed by reacting a dihydroxyl terminated compound with acetylene at160° C. in the presence of KOH. ##STR14##

A variety of aldehydes can be polymerized and fluorinated to giveperfluoropolyethers that have unique and often useful properties. Forexample, chloroacetaldehyde can be polymerized and fluorinated to giveperfluoropolychloroacetaldehyde. Similarly, dichloroacetaldehyde andtrichloroacetaldehyde can be polymerized and fluorinated to give theperfluorocarbon analogue of the polyethers. Chlorofluoroethers such asthese are potentially useful nonflammable aircraft hydraulic fluids.Their relatively high oxidative stability and low compressibility makethem attractive candidates. Other aldehydes such as acetaldehyde,trifluoroacetaldehyde and propanal can be polymerized and fluorinated togive stable polymers.

Ketals undergo a facile reversible metathesis reaction with alcohols togive polyketals as shown below in Formula (4):

    (R'O).sub.2 C(R)R''+HO(CH.sub.2).sub.n OH→HO((CH.sub.2).sub.n OC(R)(R'')O).sub.x H+2R'OH                                (6)

The list of useful ketals would include 2,2-dimethoxypropane,2,2-dimethoxybutane, 2,2-dimethoxypentane, 2,2-dimethoxyhexane,3,3-dimethoxypentane, 3,3-dimethoxyhexane as well as the diethoxy,dipropoxy, dibutoxy and diphenoxy analogues of the previously mentionedketals.

The direct reaction of a ketone with an alcohol, a reaction analogous tothe reaction of an aldehyde with an alcohol, generally works for severalisolated ketones. For this reason, the ketal is normally used.

The reaction of a trialkyl or triaryl orthoester with alcohols givesformats according to the reaction presented in Formula (5): ##STR15##Useful orthoesters include trimethylorthoformate, triethylorthoformate,tripropylorthoformate, tributylorthoformate, triphenylorthoformate,trimethylorthoacetate, triethylorthoacetate, tripropylorthoacetate,tributylorthoacetate, triphenylorthoacetate, trimethylorthopropionate,triethylorthopropionate, tripropylorthopropionate,tributylorthopropionate, triphenylorthopropionate,trimethylorthobutyrate, triethylorthobutyrate, tripropylorthobutyrate,tributylorthobutyrate and triphenylorthobutyrate.

It should be clear from the proceeding discussions that a wide varietyof linear as well as highly branched polyethers can be made using theseinterchange reactions. By carefully choosing the appropriate diol andaldehyde it is possible to prepare cyclic acetals which can often bepolymerized to give polyethers. For example, formaldehyde reacts withdiethylene glycol to give 1,3,6-trioxocane which can be polymerized togive linear polyacetals as shown in Formula (6) below: ##STR16##Similarly, the cyclic products formed by the reaction of trimethyleneglycol with dibutyl formal and the reaction of hexamethylene glycol withpropionaldehyde polymerize in the presence of an acid to given linearpolymers as described in U.S. Pat. No. 2,071,252. In general, if theglycol is 1,4-butanediol or higher a linear polymer is formed whereasglycols having fewer carbons generally form rings. If the glycol used isa polyether glycol, such as diethylene glycol or triethylene glycol, thelinear polymer represents a thermodynamically more stable structure.However, it is often possible to convert the linear polyether to thecyclic ether by vacuum pyrolysis.

Up to this point the discussion has been limited to relatively highmolecular weight materials prepared from diols. If the same reactionsare carried out using monohydridic alcohols a single compound is madewhich typically has a much lower molecular weight having essentially theformula shown after fluorination ##STR17## wherein R₁, R₂ and R₃ are thesame or different and are selected from the group consisting of --F,perfluoroalkyl of one to ten carbon atoms, which may contain etheroxygens and wherein fluorine may be optionally substituted with one ormore halogen groups other than fluorine.

For example, a monohydridic alcohol will react with an aldehyde, acetalor divinyl ether to give a new acetal.

    2ROH+HCR'O→RO--CHR'--OR                             (9)

    2ROH+(R''O).sub.2 CR'H→RO--CHR'--OR                 (10)

    2ROH+CH.sub.2 ═CHOR'OCH═CH.sub.2 →ROCH(CH.sub.3)OR'OCH(CH.sub.3)OR                  (11)

The reaction of an alcohol with a ketal will result in an interchangereaction given rise to a ketal.

    2ROH+(R''O)2CR'R'''→RO--CR'R'''--OR                 (12)

A monohydridic alcohol will react with an orthoester to give anotherorthoester.

    3ROH+(R'O).sub.3 CH→(RO).sub.3 CH                   (13)

Low molecular weight unimolecular polyethers can be made by reacting anyof the previously mentioned aldehydes, acetals, ketals or orthoesterswith a monohydridic alcohol such as methoxyethanol, ethoxyethanol,butoxyethanol, diethylene glycol methyl ether, diethylene glycol ethylether, diethylene glycol butyl ether, triethylene glycol methyl ether,triethylene glycol ethyl ether, triethylene glycol butyl ether,tetraethylene glycol methyl ether, tetraethylene glycol ethyl ether,tetraethylene glycol butyl ether, pentaethylene glycol methyl ether,pentaethylene glycol ethyl ether, pentaethylene glycol butyl ether,propylene glycol methyl ether, propylene glycol ethyl ether, propyleneglycol butyl ether, dipropylene glycol methyl ether, dipropylene glycolethyl ether, dipropylene glycol butyl ether, tripropylene glycol methylether, tripropylene glycol ethyl ether and tripropylene glycol butylether.

Low molecular weight, unimolecular perfluoropolyether fluids findnumerous application in the electronics industry. Fluorocarbon fluidsare useful as coolants and insulators in high-voltage electronicequipment, as immersion medium for leak testing, as heat transfer agentsfor vapor phase soldering, as fluids for direct cooling of electronicdevices and as thermal shock fluids. Fluorinated polyether acetals, suchas the ones described herein may also find uses as fluorocarbon bloodsubstitutes.

Conversion of the hydrocarbon polyether to a perfluoropolyether can beaccomplished by reacting the polyether with elemental fluorine. Becauseof the reactive nature of elemental fluorine, it is preferred to dilutethe fluorine with an inert gas such as nitrogen or helium. Typically,the fluorine is diluted with nitrogen and as higher degrees offluorination are achieved, the concentration of fluorine is usuallyincreased. Due to the extreme exothermicity of the reaction, thefluorination must be carried out slowly unless provisions have been madefor rapidly removing the heat of reaction. Submersion of the reactor ina cooled liquid bath is usually adequate for achieving commerciallyacceptable rates of reaction.

Fluorine gas is the preferred fluorinating agent and is commerciallyavailable at sufficiently high purity levels and at an acceptable cost.The fluorination reaction is generally carried out at a temperaturebetween -80° and +150° C., preferably between -10° and +40° C. It can becarried out in a reactor containing an ultraviolet radiation source orin the dark. Using the preferred temperature range, it is not necessaryto have an ultraviolet light source since the fluorine is sufficientlyreactive. If an ultraviolet light source is used, however, a wavelengthbetween 250 and 350 nm is preferred. When the reactor is irradiated withan external light source, a transparent window is needed which does notreact with either fluorine or hydrogen fluoride. A quartz lens coatedwith a thin film of fluorinated ethylene-propylene copolymer works well.

The fluorination reaction can be carried out in a variety of ways. Thepolyether can be coated on sodium fluoride powder to give a free-flowingpowder which can be fluorinated in either a stationary tube, in arotating drum-type reactor, or in a fluidized bed. See U.S. Pat. No.4,755,567.

Alternatively, the polyether, if soluble, can be dissolved in a solventinert to fluorine and can be fluorinated while in solution using aliquid phase fluorination reactor. See U.S. patent application Ser. No.07/250,376, entitled "Liquid Phase Fluorination", by Thomas R.Bierschenk, Timothy J. Juhlke, Hajimu Kawa and Richard J. Lagow, filedSep. 28, 1988, now abandoned, and U.S. Pat. No. 5,093,432, which is acontinuation-in-part of 07/250,376, issued to Bierschenk et al. (Mar. 3,1992), the teachings of which are incorporated by reference herein. Atypical laboratory-size reactor for example, has a volume of about 10liters and contains approximately 2 to 8 liters of a suitable solvent.Perhalogenated chlorofluorocarbons are used as the solvent.1,1,2-trichlorotrifluoroethane works well since it does not reactappreciably with fluorine when the preferred temperature range is used.

The reaction can be carried out either in a batch mode where all of thepolyether is dissolved in a solvent prior to fluorination or in acontinuous mode where the polyether is continuously being pumped intothe solvent as fluorine is being bubbled through the solution. Generallyspeaking, the continuous operation gives a preferred yield, betterproduct quality and improved rates.

If the polyether is insoluble in the liquid fluorination medium, it canstill be fluorinated in high yield as an emulsion in the liquid phasereactor. An emulsified solution of the polyether and the fluorine-inertliquid fluorination medium can either be pumped into the reactor or thereactant can be emulsified in the reactor with the fluorination mediumprior to the reaction.

An alternative method for fluorinating polyethers which are insoluble inthe liquid fluorination medium involves adding a solvent to thepolyether which allows limited solubility of polyether in the liquidfluorination medium. For clarity, 1,1,2-trichlorotrifluoroethane hasbeen selected as the liquid fluorination medium; however, other highlyfluorinated solvents can also be used. Typically, a mixture containingone part polyether, one part solvent and one part1,1,2-trichlorotrifluoroethane will give a homogeneous solution. Asolvent is selected which readily dissolves the polyether. Often it ispossible to choose a solvent which will consume little, if any, of thefluorine gas. Trifluoroacetic anhydride, trifluoroacetic acid,chloroform, 1,1,2-trichloroethylene and 1,1,2-trichloroethane workespecially well.

The polyether/solvent/1,1,2-trichlorotrifluoroethane solution is meteredinto a vigorously stirred fluorination reactor. As the polyethersolution contacts the 1,1,2-trichlorotrifluoroethane in the reactor, anemulsion is formed. The polyether droplets in the solution are in mostcases sufficiently small that they react quickly with the fluorine gaswith negligible side reactions.

When carrying out the reaction in a liquid fluorination medium, ahydrogen fluoride scavenger such as sodium fluoride or potassiumfluoride may or may not be present in the solution to scavenge theby-product hydrogen fluoride. However, the preferred mode for carryingout the reaction is with a sufficient quantity of sodium fluoride beingpresent to complex with all of the hydrogen fluoride formed. Whenfluorinating ethers in the presence of sodium fluoride, improved yieldsare obtained while chain cleavage and rearrangements are minimized. SeeU.S. Pat. No. 4,755,567, the teachings of which are incorporated hereinby reference.

Products produced using the methods just described usually have aresidual hydrogen content of 0.001% or less. In order to obtain a fluidwhich is essentially free of residual hydrogen and void of any reactiveterminal groups such as acyl fluoride groups resulting from chaindegradation reactions, a final fluorination near 175° C. with 30%fluorine for several hours works well.

The following examples will further illustrate the invention, but arenot to be construed as limiting its scope.

EXAMPLE 1

400 g butoxyethoxyethanol (2.5 mol), 48 g paraformaldehyde (1.6 mol),300 ml benzene and 5 g ion exchange resin (acid form) were placed in a 1liter stirred flask. A water separator attached to a reflux condenserwas used to collect the water produced as the alcohol and aldehydereacted. After approximately 6 hours, the reaction was complete and thesolution was filtered to remove the resin. Vacuum distillation of thesolution to 120° C. gave 414 g of a product (99% yield) which wasessentially free of benzene and unreacted starting materials.

The hydrocarbon product was fluorinated in a 22 liter stirred tankreactor which contained 6 liters of 1,1,2-trichlorotrifluoroethane and1300 g sodium fluoride powder. A gas dispersion tube in the bottom ofthe reactor provided an inlet for the fluorine and nitrogen gasses. 275grams of the hydrocarbon reactant was diluted with1,1,2-trichlorotrifluoroethane, in a separate vessel, to give a totalvolume of 700 ml. This solution was metered into the fluorinationreactor over a 20 hour period. The reactor temperature was maintained at0° C. with external cooling throughout the reaction while the fluorineflow was set at a level 10% higher than that required to theoreticallyreplace all of the hydrogens on the material entering the reactor. Uponcompletion of the reaction, the fluorine was turned off, the reactor wasremoved from the low temperature bath and purged for 30 min withnitrogen (2 liters/min) to remove the unreacted fluorine.

Filtration of the reaction product followed by distillation to removethe 1,1,2-trichlorotrifluoroethane gave 642 g of a highly fluorinatedfluid (80% yield). Treatment of the fluid at 260° C. with 30% fluorinefor several hours gave a perfluorinated fluid having essentially thefollowing structure:

CF₃ CF₂ CF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ CF₂CF₃.

The elemental analysis was consistent with the formula:

C₁₇ F₃₆ O₆

b.p. 226.5° C. ¹⁹ F NMR (δppm vs CFCl₃) -89.0, -90.7: CF₂ CF₂ O; -51.8:CF₂ O; -81.8, -83.7, -126.7: CF₃ CF₂ CF₂ CF₂ O.

EXAMPLE 2

A mixture of 400 g triethylene glycol monoethyl ether (2.2 mol), 48 gparaformaldehyde (1.6 mol), 150 ml toluene and 10 g of an acid ionexchange resin was refluxed for 6 hours in a 1 liter flask equipped witha water separator and reflux condenser. Filtration of the productfollowed by distillation gave a quantitative yield of the desiredproduct.

Fluorination of 201 g of the material in a stirred liquid fluorinationreactor containing 6 liters of 1,1,2-trichlorotrifluoroethane and 1055 gsodium fluoride gave 401 g fluid in an 18 hour reaction at 0° C.Distillation of the crude product mixture gave 355 g of theperfluorinated fluid:

CF₃ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂CF₃

The elemental analysis was consistent with the formula:

C₁₇ O₈ F₃₆

b.p. 217° C. ¹⁹ F NMR (ppm vs CFCl₃): -51-7:CF₂ O; -87.3, -90.7:CF₃ CF₂; -88.7 CF₂ CF₂ O.

EXAMPLE 3

Into a 1 liter flask were placed 600 g triethylene glycol butyl ether(2.91 mol), 74 g paraformaldehyde (2.46 mol), 150 ml benzene and 10 g ofan acidic ion exchange resin. The mixture was refluxed for 5 hours aswater was removed as the water/benzene azeotrope. Filtration of theproduct and removal of the benzene by distillation gave a 90% yield ofthe polyether. 259 grams of the product were diluted with 400 ml1,1,2-trichlorotrifluoroethane and were slowly metered into a 10° C.reactor containing 5.7 liters of 1,1,2-trichlorotrifluoroethane and 1200g sodium fluoride powder. A fluorocarbon fluid (660 g, 88.7% yield) wasobtained following filtration and removal of the1,1,2-trichlorotrifluoroethane. Fluorination of the fluid at 220° C.with 30% fluorine for 12 hours followed by distillation gave thefollowing fluid in 60% yield:

CF₃ CF₂ CF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂CF₂ OCF₂ CF₂ CF₂ CF₃

b.p. 262° C. ¹⁹ F NMR (δppm vs CFCl₃): -88.7, -90.5:CF₂ CF₂ O; -51.7:CF₂O; -81.6, -83.4, -126.5:CF₃ CF₂ CF₂ CF₂ O.

EXAMPLE 4

Into a stirred 1 liter flask equipped with a water separator werecharged 350 g tetraethylene glycol butyl ether (1.40 mol), 35 gparaformaldehyde (1.18 mol), 200 ml benzene and 10 g ion exchange resin.The mixture was refluxed until the water production ceased. Filtrationof the product followed by removal of the lights via a vacuumdistillation to 140° C. gave 343 g of a light yellow fluid.

A 306 g sample of the fluid was diluted with 450 ml of1,1,2-trichlorotrifluoroethane and slowly pumped into a -6° C. reactorover a 23 hour period. The reactor contained 1450 g of sodium fluoridepowder to react with the hydrogen fluoride formed during the reactionalong with 6 liters of 1,1,2-trichlorotrifluoroethane. Filtration of theproduct followed by distillation gave 736 g of fluid.

Treatment of the fluid at 250° C. with 30% fluorine gave a clear,odorless fluid which upon distillation gave a 52% yield of a materialhaving the following structure:

CF₃ CF₂ CF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ OCF₂CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ CF₂ CF₃

b.p. 296.7° C. ¹⁹ F NMR (δppm vs CFCl₃): -51.8:CF₂ O; -88.8, -90.6:CF₂CF₂ O; -81.7, -83.6, -126.7:CF₃ CF₂ CF₂ CF₂ O.

EXAMPLE 5

Dipropylene glycol methyl ether (300 g, 2.04 mol), 60.8 gparaformaldehyde (2.03 mol), 100 ml toluene and 5 g of an acid catalystwere mixed in a stirred 1 liter flask. After refluxing for 12 hours, thesolution was filtered and distilled to give 203 g of a fluid whichboiled at 140° C. at 0.05 mm Hg. The fluid (200 g) was mixed with 300 ml1,1,2-trichlorotrifluoroethane and 950 g sodium fluoride powder. Thereaction was complete in 18 hours after which time the solution wasfiltered and distilled to give 405 g of a clear liquid having thefollowing structure (71% yield):

CF₃ OC₃ F₆ OC₃ F₆ OCF₂ OC₃ F₆ OC₃ F₆ OCF₃

The fluid contains CF(CF₃)CF₂ OCF(CF₃)CF₂ O, CF(CF₃)CF₂ OCF₂ CF(CF₃)Oand CF₂ CF(CF₃)OCF(CF₂)CF₂ O linkages. The structure was confirmed by FNMR and elemental analysis:

¹⁹ F NMR (δppm vs CFCl₃): -47.6:CF₃ O; -54.0:CF₂ O; -80.0:CF(CF₃)CF₂ O;-82 to -87:CF(CF₃)CF₂ O; -140 to -150:CF(CF₃)CF₂ O.

EXAMPLE 6

A mixture of 300 g tripropylene glycol methyl ether (6.46 mol), 33.7 gparaformaldehyde (1.12 mol), 150 ml benzene and 3 g ion exchange resinwas refluxed for 6 hours in a 1 liter flask equipped with a waterseparator and reflux condenser. Filtration of the product followed byvacuum distillation of the lights gave 166 g of a product with a boilingpoint above 150° C. at 0.05 mm Hg.

Fluorination of 145 g of the material, dissolved in 450 ml of1,1,2-trichlorotrifluoroethane, in a stirred fluorination reactorcontaining 6 liters of 1,1,2-trichlorotrifluoroethane and 700 g ofsodium fluoride gave 244 g of a fluorocarbon product in a 20 hourreaction at -3° C. Distillation of the product gave 180 g of theperfluorinated fluid: ##STR18## where the hexafluoropropylene oxideunits are attached randomly in a head to head, head to tail and tail totail fashion.

b.p. 260.0° C. ¹⁹ F NMR (δppm vs CFCl₃):-47.3,-56.O:CF₃ O; -54.O:CF₂ O;-80.0 CF(CF₃)CF₂ O; -83.0 -85.3:CF(CF₃)CF₂ O; -145.3, -146.0:CF(CF₃)CF₂O.

EXAMPLE 7

A mixture of 600 g diethylene glycol and 30 g potassium hydroxide washeated to 160° C. in a 1 liter flask. Acetylene gas was bubbled throughthe solution as it was rapidly stirred. The reaction was stopped after48 hours and the product was extracted with water several times toremove any unreacted diethylene glycol. The product, a divinyl ether ofdiethylene glycol, was recovered by distillation (b.p. 196° C.) in aboutan 80% yield.

A 1 liter flask cooled to -10° C. was charged with 250 g triethyleneglycol ethyl ether and a catalytic amount of methane sulfonic acid. Tothis solution was added slowly 100 g diethylene divinyl ether. Followingthe addition, the flask was slowly warmed to room temperature over a 3hour period. The product was distilled to 150° C. at 0.05 mm Hg toremove any unreacted starting materials.

The product from the above reaction can be fluorinated at 20° C. usingthe procedures outlined in the previous liquid phase fluorinationexamples to give a perfluorinated fluid of the following structure:

CF₃ CF₂ O(CF₂ CF₂ O)₃ CF(CF₃)O(CF₂ CF₂ O)₂ CF(CF₃)O(CF₂ CF₂ O)₃ CF₂ CF₃

C₂₄ F₅₀ O₁₁ b.p. 300° C.

EXAMPLE 8

A mixture of 600 g 1,5-pentanediol and 30 g potassium hydroxide washeated to 160° C. in a 1 liter flask. Acetylene gas was bubbled throughthe solution as it was rapidly stirred. The reaction was stopped after40 hours and the product was washed with water and distilled to give an85% yield of pentanediol divinyl ether (b.p. 192° C.).

A 1 liter flask cooled to -12° C. was charged with 104 g pentanediol anda trace of methane sulfonic acid. To this solution was added 156 gpentanediol divinyl ether. The solution was stirred rapidly for 2 hours.Then slowly warmed to room temperature over a 6 hour period to give aviscous polymer having viscosity of 650 cst. at 100° F. (38° C.).

The product from the above reaction can be fluorinated in a liquid phasereactor containing 1,1,2-trichlorotrifluoroethane and a sufficientamount of fluorine to complex with all of the hydrogen fluoride formedduring the reaction. A perfluoropolyether having the following structureis obtained:

CF₃ CF₂ CF₂ CF₂ O(CF₂ CF₂ CF₂ CF₂ CF₂ OCF(CF₃)O)_(n) CF₂ CF₂ CF₂ CF₃.

EXAMPLE 9

A mixture of 400 g triethylene glycol ethyl ether (2.24 mol), 258 gacetaldehyde diethylacetal (1.39 mol), 300 ml benzene and 10 g acidicion exchange resin were refluxed in a 1 liter stirred flask equippedwith a continuous extractor to remove the by-product ethanol from therefluxing benzene. The solution was refluxed for 6 hours, then filteredand placed in a rotary evaporator to remove the benzene solvent.

The product was fluorinated in a 22 liter stirred tank which contained5.7 liters of 1,1,2-trichlorotrifluoroethane and 1100 g sodium fluoridepowder. The hydrocarbon, 219 g, was diluted to a volume of 700 ml with1,1,2-trichlorotrifluoroethane. The solution was slowly pumped into thefluorination reactor, which was held at -5° C., over a period of 28hours. The fluorine flow was set at a level approximately 10% higherthan that required to react with all of the organic entering thereactor. Filtration of the crude reactor product followed bydistillation yielded 224 g of a clear fluid which analyzed to be:

CF₃ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF(CF₃)OCF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂OCF₂ CF₃

¹⁹ F NMR (δppm vs CFCl₃):-86.5:OCF(CF₃); -87.4:CF₃ CF₂ O; -88.O:CF₃ CF₂O; -88.7:OCF₂ CF₂ O; -96.3:OCF(CF₃)O.

EXAMPLE 10

In an experiment very similar to the previous one, 400 g dipropyleneglycol monomethylether (2.70 mol) was reacted with 159.5 g acetaldehydediethylacetal (1.35 mol) in benzene with an acid catalyst. Fluorinationof 250 g of the material afforded 480 g of a perfluorinated fluid havingthe following structure:

CF₃ OCF₂ CF(CF₃)OCF₂ CF(CF₃)OCF(CF₃)OCF₂ CF(CF₃)OCF₂ CF(CF₃)OCF₃.

EXAMPLE 11

Butoxyethoxyethanol (400 g, 2.47 mol) was reacted with 130 g polymericchloroacetaldehyde in 150 ml benzene to give a fluid which distilled at190° C. at approximately 1 torr. The product (266 g) was mixed with 500ml 1,1,2-trichlorotrifluoroethane and pumped into a 15 literfluorination reactor containing 5.7 liters1,1,2-trichlorotrifluoroethane and 1,150 g sodium fluoride powder.Fluorine, diluted with approximately four volumes of nitrogen, wasmetered into the 0° C. reactor at a rate approximately 10% greater thanthat required to react stoichiometrically with the polyether. Theorganic feed rate was set to allow complete addition in approximately 23hours. Filtration of the product and removal of the1,1,2-trichlorotrifluoroethane via a distillation gave a fluorocarbonproduct which was further purified by a 12 hour fluorination at 200° C.with 40% fluorine. Approximately 520 g of fluid was recovered withapproximately 50% being the target material.

CF₃ CF₂ CF₂ CF₂ OCF₂ CF₂ OCF₂ CF₂ OCF(CF₂ Cl)OCF₂ CF₂ CF₂ OCF₂ CF₂ OCF₂CF₂ CF₃

b.p. 245.5° C. ¹⁹ F NMR (δppm vs CFCl₃) -73.3:OCF(CF₂ Cl)O; -81.7:CF₃CF₂ CF₂ CF₂ O; -83.3:CF₃ CF₂ CF₂ CF₂ O; -88.0 and -88.7:OCF₂ CF₂ O;-96.7:OCF(CF₂ Cl)O; -126.5:CF₃ CF₂ CF₂ CF₂ O.

EXAMPLE 12

Chloroacetaldehyde dimethyl acetal (124 g, 1 mol),1,3-dichloro-2-propanol (258 g, 2 mol) and 5 g ion exchange resin weremixed in a 1 liter stirred flask. The mixture was heated to allow themethanol formed in the reaction to slowly distill from the flask.Approximately 70 ml of methanol was recovered over a 6 hour period. Theremaining solution was vacuum-distilled and the fraction (120 g, 38%yield) boiling between 100° and 145° C. at 2 mm Hg was collected. Thefluid was shown by ¹⁹ F NMR and elemental analysis to have the followingstructure: ##STR19##

The above acetal (210 g) diluted with a small amount of chloroform and1,1,2-trichlorotrifluoroethane was metered over a 14 hour period into a22° C. fluorination reactor containing 5.7 liters of1,1,2-trichlorotrifluoroethane. The crude product was further treatedwith 30% fluorine at 200° C. for several hours to give 197 g 157% yield)of clear fluid: ##STR20## b.p.: 202° C. ¹⁹ F NMR (δppm vs CFCl₃):-64.5and -65.0(a), -71.0(d), -86.7(c) and -133.7(b) ##STR21##

EXAMPLE 13

Into a 1 liter stirred flask containing 300 ml benzene were placed 516 g1,3-dichloro-2-propanol (4 mol), 120 g paraformaldehyde (4 mol) and 10 gion exchange resin. The mixture was refluxed as the water formed duringthe reaction was continuously removed. After refluxing for 6 hours, thereaction mixture was filtered and vacuum-distilled to give 354 g of aproduct with the following structure:

(ClCH₂)₂ CHOCH₂ OCH(CH₂ Cl)₂

b.p.: 141° C./0.05 mm Hg.

The above acetal (354 g) was mixed with 70 g chloroform and 360 g1,1,2-trichlorotrifluoroethane and fluorinated over a 24 hour period at20° C. using the procedure described in the previous example. Thereaction product was concentrated and the crude product was furthertreated with fluorine at 200° C. to give 430 g of a clear fluid (69%yield) having a boiling point of 178° C.

¹⁹ F NMR (δppm vs CFCl₃): -45.5(c), -65.3(a) and -137.1(b) ##STR22##

EXAMPLE 14

A mixture of 300 g 1-propanol (5.0 mol), 231 g epichlorohydrin and 10 gion exchange resin was refluxed for 22 hours. The reaction mixture wasthen cooled, filtered and distilled to give 281 g of1-chloro-3-propoxy-2-propanol (74% yield). Reaction of this product withparaformaldehyde (2.8 mol) gave 202 g of product (69% yield) having thefollowing structure: ##STR23## b.p.: 132° C. at 2 mm Hg.

Fluorination of the above acetal in a 23 hour reaction at 20° C. gave404 g or product (81% yield) having the following structure: ##STR24##b.p.: 207° C. ¹⁹ F NMR (δppm vs CFCl₃):-46.3(g), -67.3(f), -80.4(d)-81.9(a), -84.5(c), -130.0(b) and -141.6(e) ##STR25##

EXAMPLE 15

A mixture of 600 ml ethoxyethanol, 200 g epichlorohydrin and 10 g ionexchange resin was heated to 130° C. for 20 hours. The reaction mixturewas then cooled, filtered and distilled to give 250 g of product whichwas then reacted with 116 g paraformaldehyde to give 266 g of a productboiling above 150° C. at 0.01 mm Hg.

Fluorination of 261 g of the product in a reactor containing 5 liters of1,1,2-trichlorotrifluoroethane and 1000 g sodium fluoride gave 446 g ofperfluorinated fluid of which approximately 70% had the followingstructure: ##STR26## b p. 224° C. ¹⁹ F NMR (δppm vs CFCl₃): -46.4(h),-67.6(g), -80.9(e), -87.6(a), -89.0(b,c,d), and -141.8(f) ##STR27##

EXAMPLE 16

A mixture consisting of 100 g 2-chloroethanol (12.4 mol), 573 gepichlorohydrin (6.2 mol) and 20 g of an acidic ion exchange resin wererefluxed for 24 hours. The mixture was then filtered to remove the ionexchange resin and the excess alcohol and unreacted epichlorohydrin wereremoved by distillation. The residue was distilled under vacuum and theproduct 1-chloro-3-(2-chloroethoxy)-2-propanol (804 g, 75% yield)distilled between 89° and 90° C. at 0.05 mm Hg.

Into a 1-liter stirred flask was placed 346 g1-chloro-3-(2-chloroethoxy)-2-propanol (2 mol), 90 g paraformaldehyde (3mol), 10 g ion exchange resin and 300 ml benzene. The mixture wasrefluxed for four hours as the water formed during the reaction wasremoved. The reaction mixture was filtered and distilled to give 267 gof a product (75% yield) with the following structure: ##STR28##

Fluorination of the product (660 g) in a typical reaction at 20° C. gave1086 g of a product (82% yield) having the following structure:##STR29## b.p.: 223° C. ¹⁹ F NMR: (δppm vs CFC13): -46.3(f), -67.3(e),-74.3(a), -81.0(c), -87.3(b) and -141.9(d) ##STR30##

EXAMPLE 17

Into a 1 liter flask was charged 300 g trichloropentaerythritol, (1.58mol), 150 ml of benzene, 10 g ion exchange resin and 60 gparaformaldehyde (2 mol). The mixture was refluxed as water was beingremoved continuously.

A portion of the above product, 192 g, was diluted with1,1,2-trichlorotrifluoroethane to give 210 ml of solution which waspumped into a 22° C. reactor containing 4.3 liters of1,1,2-trichlorotrifluoroethane. The reaction was complete inapproximately 8 hours. The unreacted fluorine was flushed from thereactor with nitrogen gas and the product (307 g, 87.8% yield) wasrecovered by distillation:

¹⁹ F NMR (δppm vs CFCl₃): -48.9(a), -51.1(c), -66.4(b) ##STR31##

Equivalents

Those skilled in the art will recognize or be able to ascertain using nomore than routine experimentation many equivalents to the specificembodiments of the invention described herein. Such equivalents areintended to be encompassed by the following claims.

We claim:
 1. A perfluorinated polyether having an average formula:##STR32## wherein R₁, R₂ and R₃ are the same or different and areselected from the group consisting of --F, --Cl, --CF₂ Cl, --CFCl₂,--CCl₃, perfluoroalkyl of one to ten carbon atoms andperfluoroalkoxyalkyl of one to ten carbon atoms wherein one or more ofthe fluorine atoms can be substituted by a halogen atom other thanfluorine; wherein X and Z are the same or different and are selectedfrom the group consisting of --(CF₂)_(r) COF, --(CF₂)_(r) OCF₃,--(CF₂)_(r) COOH and --C_(r) F_(2r+1-q) Cl₁, wherein r is an integerfrom 1 to 12 and q is an integer from 0 to 25; p is an integer from 1 to50, provided that the polyether includes at least one halogen atom otherthan fluorine.
 2. The perfluorinated polyether of claim 1 wherein atleast one of R₁, R₂ and R₃ contains a halogen atom other than fluorineand p is an integer between 2 and
 50. 3. A perfluorinated polyetherhaving an average formula: ##STR33## wherein R₁, R₂ and R₃ are the sameor different and are selected from the group consisting of --F, --Cl,--CF₂ Cl, --CFCl₂, --CCl₃, perfluoroalkyl of one to ten carbon atoms andperfluoroalkoxyalkyl of one to ten carbon atoms wherein one or more ofthe fluorine atoms can be substituted by a halogen atom other thanfluorine; wherein X and Z are --(CF₂)_(r) OCF₃ wherein r is an integerfrom 1 to 12 and q is an integer from 0 to 25; p is an integer from 1 to50, provided that the polyether includes at least one halogen atom otherthan fluorine.
 4. A perhalogenated polyether having an average formula:##STR34## wherein R₁, R₂ and R₃ are the same or different and areselected from the group consisting of --F, --Cl, --CF₂ Cl, --CFCl₂,--CCl₃, perfluoroalkyl of one to ten carbon atoms andperfluoroalkoxyalkyl of one to ten carbon atoms; wherein X and Z are--(CF₂)_(r) COOH wherein r is an integer from 1 to 12 and q is aninteger from 0 to 25; p is an integer from 1 to 50, provided that thepolyether includes at least one halogen atom other than fluorine.
 5. Aperhalogenated polyether having an average formula: ##STR35## whereinR₁, R₂ and R₃ are the same or different and are selected from the groupconsisting of --F, --Cl, --CF₂ Cl, --CFCl₂, --CCl₃, perfluoroalkyl ofone to ten carbon atoms and perfluoroalkoxyalkyl of one to ten carbonatoms; wherein X and Z are --C_(r) F_(2r+1-q) Cl_(q) wherein r is aninteger from 1 to 12 and q is an integer from 0 to 25; p is an integerfrom 1 to 50, provided that the polyether includes at least one halogenatom other than fluorine.